United States patent application US 2008/0019395 describes expedited communication traffic handling. A traffic block that includes an amount of communication traffic that has been received on a receive communication link at a receive rate is to be transmitted on an output communication link at an output rate. A determination is made as to whether transmission of the traffic block at the output rate would be completed before a remaining amount of communication traffic to be included in the traffic block is received at the receive rate. Transmission of the traffic block is started, before all of the traffic that is to be included in the block is received, if transmission of the traffic block at the output rate would not be completed before the remaining amount of communication traffic is received.
Conventionally, tight control of latency and jitter may be provided by way of dedicated hardware blocks that are arranged to meet specific latency and jitter requirements. The use of such dedicated hardware blocks on a single device leads to a relatively expensive and inflexible solution. In particular, in order for a given switch to be able to meet the requirements of more than one cut-through mode, a separate, dedicated hardware block is required for each cut-through mode, thereby resulting in a significant increase in cost, power consumption and real estate requirements for the switch.
A problem of the device known from US 2008/0019395 is that incoming data is first received in a receiver unit, subsequently processed in a transmission block advancing system and then stored in a transmission buffer. Such a processing system causes latency and jitter when transferring the incoming data into outgoing data.